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Omnidirectional microphones
Omnidirectional microphones are suited to recording all sounds in an area but are poor for focusing on a single subject among background noise.

Directional microphones
Directional microphones, also referred to as unidirectional, are better at picking up sounds from a particular direction and are useful in situations where there is significant background noise.

Shotgun microphones are a type of directional microphone often used in film and television production to record audio from a distance.

Cardioid microphones are another type of directional microphone that is commonly used for live music recordings and performances.

Bidirectional microphones
Bidirectional microphones are designed to pick up sounds from two directions, making them ideal for recording conversations.

Condenser microphones
Condenser microphones use the varied electrical charge of a capacitor with a diaphragm acting as one of the plates of a capacitor. The plate is biased by a fixed charge, often from a battery which also amplifies the signal.

The capacitance varies with the movement of the diaphragm in relation to the other plates providing the means to record the sound in the electrical signal.

Laser microphones
Laser microphones use the vibrations of surfaces affected by sound waves to capture sound at distances. The lasers return at different angles due to the vibration and these changes are interpreted and translated into sound waves.

Laser microphones are used in situations where sounds need to be recorded from a distance.

Ribbon microphones
Ribbon microphones are made using a thin strip of conductive metal that is suspended in a magnetic field. The ribbon is usually made from aluminum, duralumin or nanofilm.

When sound waves hit the microphone, the ribbon vibrates, which in turn produces an electrical signal.

Crystal microphone
Certain crystals change their electrical properties as they change shape. By attaching a diaphragm to a crystal, the crystal will create a signal when sound waves hit the diaphragm. These mics were very cheap to produce, and so found use in budget-friendly applications throughout the 20th century.

Microelectromechanical microphone
The microelectromechanical microphone (MEMS for short) is an evolution of the electret design, and is beginning to replace it in some cell phones and headsets. The MEMS mic can be made even smaller than electret, at just a few millimeters wide.

Electret microphone
Electret mics are used in cell phones, computers and hands-free headsets. An electret microphone is a type of condenser microphone in which the external charge is replaced with an electret material, which by definition is in a permanent state of electric polarization. They are also useful in documentary and news production, as tiny "lapel" mics which can be discreetly placed on an interview subject's clothing.

Dynamic microphone
A dynamic microphone takes advantage of electromagnet effects. When a magnet moves past a wire (or coil of wire), the magnet induces current to flow in the wire. In a dynamic microphone, the diaphragm moves either a magnet or a coil when sound waves hit the diaphragm, and the movement creates a small current.